1. Bunaithe ar an bhfigiúr thíos, faigh amach an sruth leictreach trí R1.
Ar a dtugtar:
Friotóir 1 (R1 ) = 4 Ω
Friotóir 2 (R2 ) = 4 Ω
Friotóir 3 (R3 ) = 8 Ω
Voltas leictreach (V) = 40 Volta
Ag Teastáil: Sruth leictreach trí R1
Réiteach:
Sreabhann an sruth leictreach ó phoitéinseal ard go poitéinseal íseal. Tá treo an tsrutha leictrigh sa chiorcad thuas mar an gcéanna le treo deiseal.
An sruth leictreach a shreabhann amach as an gceallraí
Ar dtús, ríomh an fhriotaíocht choibhéiseach ( R). Ina dhiaidh sin, ríomh an sruth leictreach ag baint úsáide as cothromóid dhlí Ohm :
V = IR nó I = V / R
V = voltas , I = sruth leictreach , R = an fhriotaíocht choibhéiseach
An fhriotaíocht choibhéiseach:
Tá friotóir R1 agus friotóir R2 ceangailte go comhthreomhar . An fhriotaíocht choibhéiseach:
1/R 12 = 1/R 1 + 1/R 2 = 1/4 + 1/4 = 2/4
R12 = 4/2 = 2 Ω
Tá friotóir R12 agus friotóir R3 ceangailte i sraith . Is é seo an fhriotaíocht choibhéiseach:
R = R12 + R3 = 2 + 8 = 10 Ω
An sruth leictreach a shreabhann amach as an gceallraí:
I = V / R = 40 / 10 = 4 A
Is é 4 Ampere an sruth leictreach a shreabhann amach as an gceallraí .
Voltas leictreach V ab agus V bc
ciorcan chéad riail deirtear go bhfuil ag ag aon phointe acomhail, ní mór suim na sruthanna uile atá ag dul isteach san acomhal a bheith cothrom le suim na sruthanna uile atá ag fágáil an acomhail.
Bunaithe ar chéad riail Kirchhoff , baintear an chonclúid de, má tá an sruth leictreach a shreabhann amach as an gceallraí cothrom le 4 A, go bhfuil an sruth leictreach trí ab cothrom le 4 Aimpéar, agus mar sin tá an sruth leictreach trí bc cothrom le 4 Aimpéar freisin.
Voltas leictreach V ab :
V ab = I ab R ab = (4)(2) = 8 Volta
Voltas leictreach V bc :
V bc = I bc R bc = (4)(8) = 32 Volta
Tá an ciorcad thuas ceangailte i sraith ionas go mbeidh an voltas leictreach iomlán V = V ab + V bc = 8 Volta + 32 Volta = 40 Volta.
Sreabhann an sruth leictreach trí R 1 = 4 Ω
I1 = Vab / R1 = 8 Volta / 4 Óim = 2 A
I2 = Vab / R2 = 8 Volta / 4 Óim = 2 A
Is é 4 A an sruth leictreach a shreabhann amach as an gceallraí. Nuair a shroicheann sé pointe a roinntear an sruth leictreach ina dhá leath, sreabhann an sruth leictreach 2 Aimpéar tríd an bhfriotóir R1 agus
Sreabhann an sruth leictreach 2 A tríd an bhfriotóir R2 . 2 A + 2 A = 4 A.
2. Bunaithe ar an bhfigiúr thíos, faigh amach an sruth leictreach a shreabhann tríd an bhfriotóir 4-Ω.
Ar a dtugtar:
Friotóir 1 (R1 ) = 6 Ω
Friotóir 2 (R2 ) = 4 Ω
Friotóir 3 (R3 ) = 1.6 Ω
An voltas leictreach (V) = 16 Volta
Ag Teastáil: Sreabhann an sruth leictreach trí 4 Ω
Réiteach:
Sreabhann an sruth leictreach ó phoitéinseal ard go poitéinseal íseal. Tá treo an tsrutha leictrigh sa chiorcad thuas mar an gcéanna le treo deiseal.
An sruth leictreach a shreabhann amach as an gceallraí
An fhriotaíocht choibhéiseach:
Tá friotóir R1 agus friotóir R2 ceangailte go comhthreomhar. An friotóir coibhéiseach:
1/R 12 = 1/R 1 + 1/R 2 = 1/6 + 1/4 = 2/12 + 3/12 = 5/12
R12 = 12/5 = 2.4 Ω
Tá friotóir R12 agus friotóir R3 ceangailte i sraith. An friotóir coibhéiseach:
R = R12 + R3 = 2.4 + 1.6 = 4 Ω
An sruth leictreach a shreabhann amach as an gceallraí:
I = V / R = 16 / 4 = 4 A
An voltas leictreach V ab agus V bc
Bunaithe ar chéad riail Kirchhoff, Tháinig sé ar an gconclúid, má tá an sruth leictreach a shreabhann amach as an gceallraí cothrom le 4 A, go bhfuil an sruth leictreach trí ab cothrom le 4 Aimpéar, agus mar sin tá an sruth leictreach trí bc cothrom le 4 Aimpéar freisin.
An voltas leictreach V ab :
V ab = I ab R ab = (4)(2.4) = 9.6 Volta
An voltas leictreach V bc :
V bc = I bc R bc = (4)(1.6) = 6.4 Volta
Tá an ciorcad thuas ceangailte i sraith ionas go mbeidh an voltas leictreach iomlán V = V ab + V bc = 9.6 Volta + 6.4 Volta = 16 Volta.
An sruth leictreach a shreabhann trí R2 = 4 Ω
I1 = Vab / R1 = 9.6 Volta / 6 Óim = 1.6 A
I2 = Vab / R2 = 9.6 Volta / 4 Óim = 2.4 A
Is é 4 A an sruth leictreach a shreabhann amach as an gceallraí. Nuair a shroicheann sé pointe a roinntear an sruth leictreach ina dhá leath,
Sreabhann an sruth leictreach 1.6 A tríd an bhfriotóir R1 agus sreabhann an sruth leictreach 2.4 A tríd an bhfriotóir R2 . 1.6 A + 2.4 A = 4 A.
